PALS as characterization tool in application to humidity-sensitive electroceramics

Abstract

It is shown that positron annihilation lifetime spectroscopy is a quite promising tool for nanostructural characterisation of humidity-sensitive spinel-type MgAl <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> ceramics, the results being achieved provided four-component fitting procedure with arbitrary lifetimes is applied to treat mathematically the measured spectra. It is shown that Tao-Eldrup model is adequate for calculation of nanopore size in MgAl <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> ceramics using lifetime values of the third and four components.